You must earn an "S+" rank on normal levels 1 through 45. To do this, you must get all prisms and reach the goal below a certain time limit. Do the following to save time. Edging time does not count towards the total. If you edge every time you climb, you will save between half a second and a full second each time. If you can edge, you can wait cycles until you are sure (specially in late levels that are longer) or arranged in a way that you are familiar with. If you die near the place where you respawn, you will not lose too much time. You will lose even less time if you were edging there.